What are some common pitfalls to avoid when implementing user authentication and session handling in PHP applications?

One common pitfall to avoid is not properly sanitizing user input, which can lead to SQL injection attacks. To prevent this, always use prepared statements when querying the database. 

// Example of using prepared statements to prevent SQL injection
$username = $_POST['username'];
$password = $_POST['password'];

$stmt = $pdo->prepare('SELECT * FROM users WHERE username = :username AND password = :password');
$stmt->execute(['username' => $username, 'password' => $password]);

$user = $stmt->fetch();

Keywords

SQL injection password hashing CSRF protection session hijacking secure cookie settings

Related Questions